Apparatus for performing operations on hydraulic tubing

ABSTRACT

Apparatus for performing a number of operations on hydraulic tubing in the construction of hydraulic installations is mobile and includes a mechanical bending device, a mechanical cut-off device for cutting the tubing to length, a de-burring device for removing the burrs from the ends of the tubing after it has been cut and a device for securing coupling parts to the ends of the cut-off lengths of tubing. All of these devices are driven by hydraulic drives, consisting of rams or motors and all of the drives are supplied with hydraulic fluid under pressure from a common pump through a number of separate control valves.

United States Patent Schmidt 51 Oct. 10, 1972 [S4] APPARATUS FORPERFORMING OPERATIONS ON HYDRAULIC TUBING [72] Inventor: Paul Schmidt,Hauptstrasse I50,

Saalhausen, Germany 22 Filed: Nov. 16, 1970 211 App]. N01: 89,584

[30] Foreign Application Priority Data Nov. 15, 1969 Germany ..P 19 57566.7

[52] US. Cl ..29/33 T, 29/200 8, 29/237, 29/520 [51] Int. Cl. ..B23p23/04 [58] Field of Search...29l33 T, 200 B, 282, 237, 520; 72/306 [56]References Cited UNITED STATES PATENTS 3,183,702 5/1965 Zittell ..29/33T 3,156,284 11/1964 Stanley ..29/282 Primary Examiner-Gil WeidenfeldAtlomey- Arthur O. Klein ABSTRACT Apparatus for performing a number ofoperations on hydraulic tubing in the construction of hydraulicinstallations is mobile and includes a mechanical bending device, amechanical cut-off device for cutting the tubing to length, a de-burringdevice for removing the burrs from the ends of the tubing after it hasbeen cut and a device for securing coupling parts to the ends of thecut-off lengths of tubing. All of these devices are driven by hydraulicdrives, consisting of rams or motors and all of the drives are suppliedwith hydraulic fluid under pressure from a common pump through a numberof separate control valves.

21 Claims, 6 Drawing Figures PKTE'N'TEDncT 10 km 3. 696; 481

sum 1 or 3 Atturnev INVENTOR,

PKT'E'N'TEDnm 10 I972 3, 696. 481

sum 2 or a INVENTOR BY Paul Sahm/d' MQ/QA.

APPARATUS FOR PERFORMING OPERATIONS ON HYDRAULIC TUBING When a hydraulicinstallation is being constructed it is extremely important, forsafetyin operation and to provide long working life, to ensure thatthehydraulic tubes are correctly bent and installed in anunstressedcondition, and also that the cut ends of the tubes are cleanlyde-burred. Inaccurate assembly can cause operational difficulties and,in extreme cases, tube failure. The hydraulic devices in theinstallation are easily damaged by metal chips deriving from burrsformed on the tube ends when the tubes are cut off to length, usually'bya saw.

To instal hydraulic tubes in a stress-free condition they have to be cutprecisely to the correct lengths. In some cases the tubes are simplysawn off by hand, after which the cut ends are finished, that is to sayare cleaned up, by hand, but this is a highly uneconomical method. Tubebending can also be done" by hand, but to obtain an accurate tube bend,in whichthe tubeis not flattened, involves special precautions, forexample the tube can be filled with sand and the ends closed by weldingbefore making the bend. Even so it is difficult to form a bend by handwhich has thequality of a machine made bend. Finally the welded-up endsof the tube have to be cut off.

If the hydraulicfitterwishes to bend, cutoff and deburr the tubes byusing machinery, hehas to leave the site of the installation andtransport the tubes to machines, which are usually at some distancefromthe site, if they are available in the locality at all. His onlyalternative is to bend, cut and finish the tubes by hand.

Even if machines are available the transportation of bent hydraulictubing is often cumbersome and time consuming. The hydraulic tubes haveto be dimensioned accurately on the site,that is to say they have to beaccuratelyfitted. In some cases the hydraulic installation can 'bepre-assembled in the manufacturers works. However in some cases thiscannot bedone-and it is necessary to'transport machines, suitable forcarrying out the necessary operations on'hydraulic tubing, to theerection site. This is often just as inconvenient and time consuming astransporting thebent tubes to-alo-' cation where machines are them.

The object of the present invention is to provide a mobile unit whichcan easily be transported to an erection site and which is capable ofperforming, rapidly and accurately the operations of tube bending,cutting to length, de-burring and securing couplingsto the tube ends. mg I,

To this end, accordingto this "invention, apparatus for performingoperations on hydraulic tubing is mobile and includes a mechanicalbending device, a mechanical cut-off device, a de-burring device anda'device for securing coupling parts to the ends of cut-off lengths oftubing.

The mobile unit is easy to propel by hand to the erection site and ofwide applicability.

Each of the devices for bending, for cutting off and for de-burring thetubing preferably has its own hydraulic drive. The mobile apparatuspreferably has a single source of hydraulic power for driving all thedevices. In this respect the apparatus contrasts with conventional tubefitting machinery. A conventional bending available for operating onmachine is usually driven hydraulically, whereas cutting-off andde-burring"machinesare almost always driven electrically.

According to afurther feature of the invention the several hydraulicdevices of the'mobile'apparatus are an supplied with'hydraulic fluidunder pressure by a single, hydraulic pumpfHowever this pump need not becapable of producing a high'output, because the several devices, forbending, cutting-offand de-burring, are not operated simultaneously. Theoperator uses the devices one after the other, and consequently thehydraulic pump need develop'a power output only sufficient for thedevice having the greatest consumption. A comparatively'small'hydraulicpump can therefore be used. I

For cutting-off the lengths of hydraulic tubing the mobile apparatus maybe provided with a circular saw whichis driven by a hydraulic motor andis advanced towards the tubing by the piston rod of a hydraulic ram.

The hydraulic motor is then connected hydraulically in series with'theram, so that the'motorfunctions in effect as a pump for the ram, thetwodevices acting in synchronization with each other. For cutting thinwalled tubing, which requires a low saw speed to obtain a clean cut, thespeed of. the hydraulic motor is preferably clamped'between two'claimjaws, at least one of which is spring-loaded towards'a closed positionand is'connected'to a singleacting hydraulic ram by which it isretracted.-This arrangementensures'that the tubing is held'byspringpressure only, the retracting hydraulic ram being inoperation'only briefly, when the operator is inserting or removing the'tubing.

For de-burring the tube ends, afte'r'cutting off, the mobile apparatuspreferably has two "milling cutters, one being a countersinkcutter'having external cutting teethand the other'bein'g female andhaving internal cutting teeth. This allows the operatorto de-b'urr thetube and internally by engaging itby hand with'the external cuttingteeth, and'de-burr the tube ndexternally by engaging it with theinternal cutting teeth.

For bending hydraulic tubing the mobile apparatus preferably has arotatable 'mandre l w'ith a'grooved'edge to mate with the periphery'ofthe particularhydraulic tubing being bent. The radius of the mandrelcorresponds 'to the desired radius of bend. The rotatablemandrel-cooperates with a stationary thrust guide and a pivoted thrustguide which swings aboutthe axis of the rotatable mandrel. Initially thetwo thrust guides are situated adjacent each other. The operatorintroduces the hydraulic tube between the rotatable mandrel and the twothrust guides. The tube is bent by swinging the pivoted thrust guidearound the mandrel. Flattening of the tube is largely prevented by thefact that both the mandrel and the thrust guides have grooved edges,corresponding in section to the cross section of the tube. Flattening ofthe tube during bending is further prevented by providing the bendingdevice with an auxiliary, internal mandrel, which is inserted into thetube before bending. The auxiliary mandrel can if desired be insertedinto the end of the tube which moves as the tube is bent so that theauxiliary mandrel acts as a calibrating mandrel.

During the bending operation the auxiliary, internal mandrel becomesjammed inside the tube. A hydraulic retraction device is preferablytherefore provided, for extracting the auxiliary mandrel from the tube.The retraction device is preferably in the form of a singleactinghydraulic ram, the return movement being effected by a return spring.

The mobile apparatus is provided with a device for securing a couplingpart such as a union nut and olive to each tube end. The purpose of thisis to facilitate the subsequent making of the tube joints duringconstruction of the hydraulic installation.

The device of securing a union nut and olive to the tube end ispreferably arranged as follows: A holder in the form of a die plate isprovided for holding the end of the tube; the operator mounts a unionnut and an olive on the end of the tube, and introduces the tube endinto the holder. The device has a press tool in the form of a hollowended plunger which applies a squeezing thrust to the olive so that theolive cuts into the outer periphery of the tube, forming a groove, theapplied thrust at the same time forming a bulge in the wall of the tube.The hollow ended plunger is mounted on the end of the piston rod of ahydraulic rarn. The press tools are interchangeable, the operatorselecting a tool to suit the diameter of the tube being operated upon.The holder, for holding the hydraulic tube, in the form of an insertsupport and is also exchangeable, so that the operator can select aninsert also to suit the diameter of the tubing.

The squeezing of the olive into the wall of the tubing must be done withprecision, so as not to damage the tubing and so that the bulge formeddoes not interfere when the hydraulic joint is subsequently made. Thehydraulic thrust applied to the press'tool must therefore be adjustablewith precision. For this purpose the hydraulic ram is preferablyprovided with an adjustable pressure relief valve, allowing the operatorto adjust the highest hydraulic pressure reached in the ram, to suit theparticular hydraulic tubing.

The adjustable pressure relief valve is preferably arranged as follows:The pressure relief valve has a closure member which is loaded towardsthe closed position by a spring, the spring pressure of which isadjustable by changing the position of a push rod which is mounted sothat it can slide in and out of a housingggf;

the valve. The push rod loads the spring. The position of the push rodis determined by the width of the insert which holds the hydraulic tube,the end of the push rod resting against the edge of the insert. Thisarrangement automatically adjusts the ram pressure to suit theparticular tube diameter, by adjusting the response pressure of thepressure relief valve, in that when the operator instals the appropriatetube holder insert, to suit the particular hydraulic tubing diameter,this automatically adjusts the highest hydraulic pressure which will bedeveloped in the cylinder during the squeezing of the olive.

The swinging of the arm 2d is brought about by a singlean olive and aunion nut;

FIG. 5 shows a detail of a part of the apparatus for securing thecoupling parts shown in FIG. 4 on the end of the tubing; and,

FIG. 6 shows further details of the part of the apparatus shown in FIG.5;

As shown in FIG. 1, the apparatus is mobile and is in the form of a boxshaped unit I mounted on wheels la and 1b, The wheels lb have a castoraction, so that the mobile unit 1 can easily be moved by hand, by meansof a rigid handle 1e, and be steered to the site of operations.

The mobile unit 1 includes a cut-off device 2 for cutting hydraulictubing A into lengths, a de-burring device 3 for removing the burrs fromthe cut ends of the lengths of hydraulic tubing, a bending device 4 forbending the tubing and a device 5 for mounting coupling parts in theform of an olive and a union nut on the cut and de-burred end of thehydraulic tubing A. The mobile unit 1 also contains drawers (not shown)for containing tools and electrical power cables.

The cut-off device 2 consists essentially of V-section clamp jaws 2a and2b between which the hydraulic tubing A is clamped for cutting to lengthby a circular saw 2c. The saw 20 is mounted on the end of an arm 211which is pivoted in bearings 2e fixed to the frame of the apparatus. Thesaw is driven by a hydraulic motor 2f.

acting hydraulic ram 2g, which is pivoted in the bearing 2h fixed to theframe of the apparatus.

The V-section clamp jaw 2a is fixed to the outer face of the end wall 10of the mobile unit 1. The other clamp jaw 2b slides up and down along aguide rail 2i, being movable by a single-acting hydraulic ram 2j, andtwo compression springs 2k which are supported on brackets 2m fixed tothe outer face of the end wall 1c. The springs 2k are guided by guiderods Zn. The springs 2k act to close the jaws and the ram 2j to openthem against the springs.

The device 3 for de-burring the cut ends of the hydraulic tubing Acomprises two milling cutters 3a and 3b which rotate in bearings fixedto a side wall lg of the mobile unit 1. The milling cutters 3a, 3b mayproject outwards from the sidewall lg, but preferably they are recessesin this wall, to reduce risk of injury to the operator. A recessedinstallation prevents any contact between the milling cutters and theoperator, unless the operator deliberately inserts a hand into therecess. The milling cutter 3b has a male conical shape, that is to sayit has the shape of a countersink cutter, and is used for de-burring theinner edge of the cut end of the hydraulic tubing A. On the other handthe milling cutter 3a has a female cone and is used for removing theburr from the outer edge of the cut end of the tube. The two millingcutters 3a and 3b are driven directly to rotate in the same direction byhydraulic motors 3c and 3 d.

The tube bending device 4 consists essentially of a tube bending mandrel40, which may be fixed but is preferably rotatable. The tube bendingmandrel 4c cooperates with a further mandrel 4d which is connectedthrough a mandrel rod 43 to a hydraulic drive assembly 4h.

The assembly 4h consists of a hydraulic cylinder 4i.

containing a piston 4j loaded by a compression spring 4k. The movementof the piston 4], towards the tube bending mandrel 4c, is limited by anadjustable end stop in the form of a screw 4m. The mandrel rod 4g isconnected to the piston 4j by a pin 4n which moves in a longitudinalslot in the wall of the cylinder 41'.

The tubing A is wrapped around the mandrel 40 by two thrust guides 4aand 4b. The thrust guide 4a is fixed in position to the top wall If ofthe mobile unit 1. The other thrust guide 4b is mounted on'a pivoted arm4f which is rotated about its pivot by a single-acting or double-actinghydraulic ram, or by a high torque hydraulic motor 4e. The tube bendingmandrel 4c and the two thrust guides 4a, 4b have grooved edges to matchthe cross section of the tube A, to prevent flattening of the tubeduring bending.

If necessary the mandrel 40 can have a working surface of a materialwhich has a high coefficient of friction, whereas the thrust guides 4a,4b have working surfaces which present a low coefficient of friction incontact with the tube A. Consequently when the tube is being bent theouter surface of the tube is not damaged by abrasion where the thrustguides 4a, 4b slide along the surface of the tube.

The device 5 is for mounting an olive and union nut on the cut end ofthe hydraulic tubing A, as a preparation for the subsequent making ofthe hydraulic joint.

FIG. 4 shows the construction of the subsequently made hydraulic jointwhich is of the usual cone and olive type. An externally threaded,double-ended connection piece 5c is screwed into a bore in the wall of ahydraulic device, for example a valve, or a pump, or a hydraulicaccumulator. The projecting end of the connection piece St has aninternally conical bore. On to the projecting end of the connectionpiece 50 a union nut 5a containing an olive 5b is screwed. In thisoperation the union nut squeezes the olive, which cuts into the end ofthe hydraulic tubing A, making a tight joint.

For mounting the union nut 5a an olive 5b on the cut end of the tubingA, the device 5 operates as follows: A frame 5f fixed to the upper wallIf of the mobile unit 1 supports a holder or die plate 5d, whichcontains an insert support 5e, as shown in FIGS. 1, 5 and 6. The insertsupport Se is exchangeable, that is to say a number of insert supports5e are provided, each to suit hydraulic tubing of a particular externaldiameter. The die plate or holder 5d is dimensioned to take anyof theinsert supports 52. The operator selects the appropriate support 52, tosuit the particular cut piece of tubing, and inserts it into the holder5d. The holder 5d has a slot 53 of a width sufficient to accommodatehydraulic tubing A of the greatest expected diameter. On the other handthe selected insert support 5e has a slot 5h the width of which matchesthe external diameter of the particular piece of hydraulic tubing Awhich is being operated on. That is to say the slot 5h is wide enough toallow easy introduction of the particular piece of hydraulic tubing A.

To operate the device 5, the operator first of all mounts a union nut 5aand an olive 5b on to the cut end of the hydraulic tubing A. He thenintroduces the tubing A into the slot 5h so that the union nut 50 restsagainst the surface of the insert support Be, as shown in FIG. 6. Thecut end of the tubing A projects a little beyond the union nut. Theoperator then actuates a double-acting hydraulic ram 5i, on theprojecting end of the piston rod of which a hollow ended plunger Sj ismounted. The hydraulic pressure in the ram 5i thrusts the plunger 5j sothat its hollow nose enters the union nut 5a, squeezing the olive 5b sothat it cuts into the wall of the hydraulic tubing, so that when thehydraulic joint is subsequently made the olive 5b cannot slip on the endof the tubing. The hollow end of the plunger 5 j is made internallyconical for this purpose. Its outer diameter is somewhat less than theinternal diameter of the threaded part of the union nut 5a. The hollowended plunger 5j is exchangeable, so that the operator can select theappropriate plunger for the particular diameter of hydraulic tubing.

In this operation it is important to ensure that the hydraulic pressurein the ram Si is exactly right, so that exactly the correct amount offorcing-in of the olive and bulging out of the tube wall is obtained.Adjustment of the hydraulic pressure in the ram Si is provided asfollows: The cylinder 51" is connected to the inlet of a pressure reliefvalve 5m, which has a housing 5n containing a valve closure member 5ploaded by an adjustable compression spring Sq. The pressure relief valve5m has an outlet connected to an oil reservoir 6a. When the parts are inthe positions shown in FIGS. 5 and 6, the valve closure member 5p blocksthe inlet of the valve. The compression spring Sq is adjustable by meansof a push rod 5r which slides through a bore in the housing 5n. When thedevice is in operation the thrust of the compression spring Sq isadjusted, to suit the particular hydraulic tubing A, by the position ofthe push rod 5r.

The position of the push rod Sr is determined as follows: On the end ofthe push rod remote from the housing 5n there is a roller 5s whichengages one edge 52 of the insert support 5e. The different insertsupports 5e are of different widths, and consequently when the insertsupport Se is exchanged for a different one, the piston push rod 5rassumes a different position. Adjustment of the spring load on the valveclosure member 5p, and consequently adjustment of the hydraulic pressurein the cylinder Si, is therefore obtained automatically when a differentinsert support Se is selected by the operator. The widths of the insertsupports 5e are made so that the thrust applied by the hollow endedplunger 5j is always exactly suited to the particular hydraulic tubewhich fits the slot of tlie insert support.

The oil reservoir 6a supplies oil to a hydraulic pump assembly 6 whichsupplies all the hydraulic rams 2g, 2j and Si as well as the hydraulicmqtors 3a, 3b and 4e. The pump assembly 6 consists of a hydraulic pump6b, which draws oil from the reservoir 6a and delivers it to the variousrams and motors, and an electric motor 6c, which drives the pump. Theoil supplied under pressure to each ram or motor is controlled by amanually operated control valve. All the control valves are connected inparallel, giving each of the devices operated in effect its ownindependent hydraulic circuit. The

ram 2g and the motor 2f are served by a hydraulic circuit 2p controlledby a control valve 2q. The ram 2j is served by a hydraulic circuit 2r,controlled by a control valve 2s. The motors 3a and 3b are served by ahydraulic circuit 3e, controlled by a control valve 3f. The oil motor 40and the ram 4h are served by a hydraulic circuit 4p, controlled by acontrol valve 4q. The ram Si is served by a hydraulic circuit 5kcontrolled by a control valve 5v.

When the mobile unit is put into operation, it is wheeled to thelocation where it is required. The operator first of all bends thehydraulic' tubing A using the bending device 4, and then cuts it off tolength using the cut-off device 2. After de-burring the cut ends usingthe de-burring device 3, the union nut and olive are mounted on the pipeends by means of the device 5.

The bending process is conducted as follows: The tubing A is insertedbetween the thrust guides 4a, 4b, which are initially situated adjacenteach other, and the bending mandrel 4c, the tube being pushed over thesmaller mandrel 4d. The operator actuates the control valve 4q, startingthe high torque motor 4e, which swings the pivoted arm 4d about the axisof the bending mandrel 40 so that the thrust guide 4b wraps the tubing Aaround the mandrel 40. This movement is continued until the tube hasbeen bent through an angle somewhat greater than the desired final bendangle, so that when the tubing is released it returns elastically toform the desired bend angle. The mandrel 4d acts as a calibratingmandrel, and in particular prevents the tube from flattening when a bendof small radius is formed. The calibrating mandrel 4d becomes jammed inthe tube during the bending. It is extracted by the ram 4h. If desiredthe ram 4h can be mounted on the pivoted arm 4d, the calibrating mandrel4d then being inserted into the moving end of the tube. In this case thecalibrating mandrel 4d is extracted from the tube progressively duringthe bending, calibrating the tube progressively without any risk of anexcessive bending stress being applied to the mandrel rod 4g. For thispurpose, the ram 4h is connected into the hydraulic circuit 4b in serieswith the motor 42. The motor 4e produces a very high torque, eitherdirectly or through a speed reduction gear. With the motor 4ehydraulically in series with the cylinder assembly 4h, the motor 4egoverns the movement of the calibrating mandrel 4d so that the mandrel4d is extracted from the, tube in synchronization with the rotation ofthe high torque motor 4e.

However in the present example the calibrating mandrel 4d is in thestationary end of the hydraulic tubing A. In this case the calibratingmandrel 4d remains in its initial position, limited by the adjustmentscrew 4m, until after the bending of the tube has been completed. Assoon as the bending has been completed the operator actuates the controlvalve 4q, which can for example be a multi-path valve, with the resultthat the motor 4e, which can for example be reversible, swings thepivoted arm 4d back to its initial position. At the end of this movementthe pivoted arm 4d is stopped by the thrust guide 4a, and the motor 4eis prevented from rotating further. Hydraulic presure builds up in themotor 4e, opening a pressure relief valve (not shown) releasing a streamof oil which passes through the pressure relief valve and actuates theram 4h, which automatically extracts the calibrating mandrel 4d from thehydraulic tubing A. The hydraulic pressure is then removed from the ram,for example by further actuation of the control valve 4q, and thehydraulic circuit 4p which serves the device 4 is closed.

After the bending, the hydraulic tubing A is cut off to length using thecut-off device 2, unless this has already been done. For this purposethe operator actuates the control valve 2s, applying hydraulic pressureto the ram 2j and lowering the V-section clamp jaw 2b against the actionof the springs 2k so that the hydraulic tubing A can be introducedbetween the two clamp jaws 2a and 2b, up against an end stop (notshown). Further actuation of the control valve 2s releases the pressurein the ram 2j, allowing the springs 2k to lift the lower clamp jaw 2b,so that the hydraulic tubing A is gripped, ready for cutting to length.

With the hydraulic tubing A firmly clamped in place, the operatoractuates the control valve 2q, energizing the motor 2f. Rotation of themotor 2f delivers oil under pressure to the hydraulic ram 23, which isconnected hydraulically in series with the motor 2f. The ram 2g, swingsthe arm 2d and advances the rotating saw 20 against and through thetubing A, cutting it off to length. The movement of the pivoted arm 2d,or of the circular saw 2c, actuates a switch not shown) which starts asupply of coolant for the saw blade. The coolant is supplied by acoolant pump from a coolant storage tank, which contains a filter forfiltering the coolant. The coolant is delivered through a nozzleaccurately to the cut. As soon as the cut has been completed, thepivoted arm 2d is returned to its initial position, by a return spring,tripping a switch which automatically stops the flow of coolant. Afterretracting the ram 2j the operator can remove the hydraulic tubing Afrom between the two clamp jaws 2a and 2b.

It should be observed that risk of injury to the operator from thecircular saw is minimized, in that the saw blade 2c is initiallyretracted behind the front wall 1c of the mobile unit 1. The saw bladeadvances through a narrow slot in the front wall 1c, to cut the tubingA. The front wall 10 has a bulge which acts as a guard during thecutting operation, and a recess which accommodates the tubing A in sucha way that the saw blade 2c never projects outwards beyond the plane ofthe wall 10.

When cutting thin walled hydraulic tubing, a clean cut can only beobtained if the saw blade 2c is rotated comparatively slowly. The motor2f is therefore provided with a throttle or restricted orifice, as asimple method of reducing the saw blade speed.

After the cutting operation the cut ends of the hydraulic tubing A haveto be de-burred. The operator actuates the control valve 3f, energizingthe motors 3c and 3d, and then applies the cut ends of the tube by handfirst to the milling cutter 3b, to remove the inner burr, and then tothe female cutter 3a to remove the outer burr, or vice-versa.

After de-burring the cut ends of the tubing, the operator uses thedevice 5 for mounting a union nut and an olive on the end of the tubing.For this purpose the operator selects the appropriate insert supportSee, suitable for the particular tube diameter, and inserts it in theholder 5d. He also mounts the appropriate hollow ended plunger 5j on theend of the piston rod of the ram i. After mounting a union nut 5a and anolive 5b on each end of the hydraulic tube A, the operator introduceseach end of the tube in turn into the support 5e and energizes the ramSi by actuating the control valve 5s.

1 claim:

1. Apparatus for performing operations on hydraulic tubing, saidapparatus including a frame, means for mobilizing said frame, said framehaving mounted thereon tube bending means, tube cut-off means forcutting off lengths of said tubing, means for de-burring the ends ofsaid cut-off lengths of tubing, and means for securing coupling parts tosaid ends, mechanical drive means mounted on said frame and meansoperatively connecting said mechanical drive means to said bendingmeans, said cut-off means, said de-burring means and said means forsecuring coupling parts.

2. Apparatus as claimed in claim 1, wherein said mechanical drive meansincludes a plurality of separate hydraulic drive means and meansoperatively connecting said hydraulic drive means to said bending means,said cut-off means and said de-burring means.

3. Apparatus as claimed in claim 2, wherein said mechanical drive meansfurther includes a single hydraulic pump and means operativelyconnecting said pump to each of said plurality of hydraulic drive means.

4. Apparatus as claimed in claim 1, wherein said bending means includesa tube bending mandrel, means defining a peripheral groove in saidmandrel, means rotatably mounting said mandrel, a first thrust guide,means stationarily mounting said first thrust guide, a second thrustguide, means pivotally mounting said second thrust guide and means forswinging said second thrust guide about the axis of said rotatablemandrel.

5. Apparatus as claimed in claim 4, wherein said bending means furtherincludes a calibrating mandrel and means mounting said calibratingmandrel for insertion in said tubing when said tubing is held betweensaid bending mandrel and said thrust guides.

6. Apparatus as claimed in claim 5, further comprising means forretracting said calibrating mandrel to withdraw said mandrel from saidtubing.

7. Apparatus as claimed in claim 6, where said retracting means includeshydraulic ram means and means operatively connecting said ram means tosaid calibrating mandrel.

8. Apparatus as claimed in claim 7, wherein said hydraulic ram means issingle-acting and includes a cylinder, a piston and compression springmeans within said cylinder acting on said piston to move said piston ina direction opposite to that in which said ram is single-acting.

9. Apparatus as claimed in claim 1, wherein said cutoff means includescircular saw means, first mounting means for mounting said circular sawmeans for rotation about an axis, second mounting means mounting saidfirst mounting means for advancing and retracting movement lateral tosaid axis to advance said saw to cut said tubing, a hydraulic motor,means operatively connecting said hydraulic motor to said saw to rotatesaid saw, -a hydraulic ram, means operatively connecting said hydraulicram to said second mounting means, means hydraulically connecting saidhydraulic motor in series with said ram and hydraulic pump means forsupplying hydraulic fluid to said motor and thence to said ram.

10. Apparatus as claimed in claim 9, wherein said hydraulic motorincludes throttling means to limit the speed of rotation thereof.

11. Apparatus as claimed in claim 9, wherein said hydraulic ram issingle-acting and includes return spring means.

12. Apparatus as claimed in claim 9, further comprising clamping meansfor holding said tubing while said tubing is cut by said saw, saidclamping means including first and second clamp jaws, means fixedlymounting said first jaw, means movably mounting said second jaw formovement towards and away from said first jaw, spring means for movingsaid second jaw towards said first jaw and hydraulic ram means formoving said second jaw away from said first jaw against the action ofsaid spring means.

13. Apparatus as claimed in claim 1, wherein said deburring meansincludes a countersink milling cutter for de-burring said cut-off tubeend internally, a female conical milling cutter for de-burring' saidcut-off tube end externally and means for rotating said milling cutters.

14. Apparatus as claimed in claim 13, wherein said means for rotatingsaid milling cutters includes a first hydraulic motor, a secondhydraulic motor, means operatively connecting said first hydraulic motorto said countersink milling cutter, means operatively connecting saidsecond hydraulic motor to said female conical milling cutter, meanshydraulically connecting said first and second hydraulic motors inseries with each other and means for supplying hydraulic fluid underpressure to one of said motors.

15. Apparatus as claimed in claim 1, wherein said means for securingcoupling parts to said tubing includes a press tool and a die plate forsecuring an olive to said tubing.

16. Apparatus as claimed in claim 15, wherein said press tool includes ahydraulic ram, a piston rod extending from said ram, a press tool bit,and means detatchably mounting said press tool bit on said piston rodwhereby said press tool bit is exchangeable.

17. Apparatus as claimed in claim 16, wherein said die plate includes aninsert support and means detatchably mounting said insert support onsaid die plate whereby said insert support is exchangeable.

18. Apparatus as claimed in claim 17, wherein said hydraulic ram havingsaid piston on which said pressure tool is mounted includes adjustablepressure relief valve means.

19. Apparatus as claimed in claim 18, wherein said adjustable pressurerelief valve means includes a valve seat, a valve closure member, springmeans biasing said closure member towards said seat and means foradjusting the force exerted by said spring means, said ad justing meansincluding a push rod, means mounting said push rod in engagement withsaid spring means and for sliding movement in and out of said valve andmeans engaging said push rod with said insert support whereby theposition of said push rod is dependent upon the width of said insertsupport and the position of said push rod adjusts the force exerted bysaid spring means.

11 20. Apparatus as claimed in claim 19, further comprising a roller andmeans rotatably mounting said roller on one end of said push rod, saidroller engaging said insert support.

21. Apparatus as claimed in claim 20, wherein said insert supportincludes means defining a sloping edge, said sloping edge beingcontacted by said roller.

1. Apparatus for performing operations on hydraulic tubing, saidapparatus including a frame, means for mobilizing said frame, said framehaving mounted thereon tube bending means, tube cutoff means for cuttingoff lengths of said tubing, means for deburring the ends of said cut-offlengths of tubing, and means for securing coupling parts to said ends,mechanical drive means mounted on said frame and means operativelyconnecting said mechanical drive means to said bending means, saidcut-off means, said de-burring means and said means for securingcoupling parts.
 2. Apparatus as claimed in claim 1, wherein saidmechanical drive means includes a plurality of separate hydraulic drivemeans and means operatively connecting said hydraulic drive means tosaid bending means, said cut-off means and said de-burring means. 3.Apparatus as claimed in claim 2, wherein said mechanical drive meansfurther includes a single hydraulic pump and means operativelyconnecting said pump to each of said plurality of hydraulic drive means.4. Apparatus as claimed in claim 1, wherein said bending means includesa tube bending mandrel, means defining a peripheral groove in saidmandrel, means rotatably mounting said mandrel, a first thrust guide,means stationarily mounting said first thrust guide, a second thrustguide, means pivotally mounting said second thrust guide and means forswinging said second thrust guide about the axis of said rotatablemandrel.
 5. Apparatus as claimed in claim 4, wherein said bending meansfurther includes a calibrating mandrel and means mounting saidcalibrating mandrel for insertion in said tubing when said tubing isheld between said bending mandrel and said thrust guides.
 6. Apparatusas claimed in claim 5, further comprising means for retracting saidcalibrating mandrel to withdraw said mandrel from said tubing. 7.Apparatus as claimed in claim 6, where said retracting means includeshydraulic ram means and means operatively connecting said ram means tosaid calibrating mandrel.
 8. Apparatus as claimed in claim 7, whereinsaid hYdraulic ram means is single-acting and includes a cylinder, apiston and compression spring means within said cylinder acting on saidpiston to move said piston in a direction opposite to that in which saidram is single-acting.
 9. Apparatus as claimed in claim 1, wherein saidcut-off means includes circular saw means, first mounting means formounting said circular saw means for rotation about an axis, secondmounting means mounting said first mounting means for advancing andretracting movement lateral to said axis to advance said saw to cut saidtubing, a hydraulic motor, means operatively connecting said hydraulicmotor to said saw to rotate said saw, a hydraulic ram, means operativelyconnecting said hydraulic ram to said second mounting means, meanshydraulically connecting said hydraulic motor in series with said ramand hydraulic pump means for supplying hydraulic fluid to said motor andthence to said ram.
 10. Apparatus as claimed in claim 9, wherein saidhydraulic motor includes throttling means to limit the speed of rotationthereof.
 11. Apparatus as claimed in claim 9, wherein said hydraulic ramis single-acting and includes return spring means.
 12. Apparatus asclaimed in claim 9, further comprising clamping means for holding saidtubing while said tubing is cut by said saw, said clamping meansincluding first and second clamp jaws, means fixedly mounting said firstjaw, means movably mounting said second jaw for movement towards andaway from said first jaw, spring means for moving said second jawtowards said first jaw and hydraulic ram means for moving said secondjaw away from said first jaw against the action of said spring means.13. Apparatus as claimed in claim 1, wherein said de-burring meansincludes a countersink milling cutter for de-burring said cut-off tubeend internally, a female conical milling cutter for de-burring saidcut-off tube end externally and means for rotating said milling cutters.14. Apparatus as claimed in claim 13, wherein said means for rotatingsaid milling cutters includes a first hydraulic motor, a secondhydraulic motor, means operatively connecting said first hydraulic motorto said countersink milling cutter, means operatively connecting saidsecond hydraulic motor to said female conical milling cutter, meanshydraulically connecting said first and second hydraulic motors inseries with each other and means for supplying hydraulic fluid underpressure to one of said motors.
 15. Apparatus as claimed in claim 1,wherein said means for securing coupling parts to said tubing includes apress tool and a die plate for securing an olive to said tubing. 16.Apparatus as claimed in claim 15, wherein said press tool includes ahydraulic ram, a piston rod extending from said ram, a press tool bit,and means detatchably mounting said press tool bit on said piston rodwhereby said press tool bit is exchangeable.
 17. Apparatus as claimed inclaim 16, wherein said die plate includes an insert support and meansdetatchably mounting said insert support on said die plate whereby saidinsert support is exchangeable.
 18. Apparatus as claimed in claim 17,wherein said hydraulic ram having said piston on which said pressuretool is mounted includes adjustable pressure relief valve means. 19.Apparatus as claimed in claim 18, wherein said adjustable pressurerelief valve means includes a valve seat, a valve closure member, springmeans biasing said closure member towards said seat and means foradjusting the force exerted by said spring means, said adjusting meansincluding a push rod, means mounting said push rod in engagement withsaid spring means and for sliding movement in and out of said valve andmeans engaging said push rod with said insert support whereby theposition of said push rod is dependent upon the width of said insertsupport and the position of said push rod adjusts the force exerted bysaid spring means.
 20. Apparatus as claimed in claim 19, furthercomprising a roller and means rotatably mounting said roller on one endof said push rod, said roller engaging said insert support. 21.Apparatus as claimed in claim 20, wherein said insert support includesmeans defining a sloping edge, said sloping edge being contacted by saidroller.